View Compilation Error

0_0_10912645_423.cpp: In function `ll solve(ll)':
0_0_10912645_423.cpp:17: error: call of overloaded `abs(long long int)' is ambiguous
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/stdlib.h:363: note: candidates are: int abs(int)
0_0_10912645_423.cpp:7: note:                 ll abs(ll)
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/c++/3.4.2/cstdlib:153: note:                 long long int __gnu_cxx::abs(long long int)
GCC/bin/../lib/gcc/mingw32/3.4.2/../../../../include/c++/3.4.2/cstdlib:123: note:                 long int std::abs(long int)